200-901 Understanding and Using APIs Practice Question
An engineer is writing a script that calls the Cisco DNA Center API to create a new site. The API requires the request body to be encoded as JSON. Which HTTP request header should the script set so the server interprets the payload correctly?
⚠ Common exam trap
Watch out — candidates often confuse Accept, which describes what the client wants back, with Content-Type, which describes what the client is sending.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Content-Type: application/json
Content-Type describes the media type of the request body, which is exactly what a server needs in order to parse a JSON payload. Cisco DNA Center's create-site operation expects application/json, so the client must send that header or risk a 415 error. Accept negotiates the response format, Authorization supplies credentials, and Content-Length must be a byte count, so none of those substitutes for declaring the request body encoding.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Authorization: Bearer <token>
Why it's wrong here
The Authorization header carries credentials, such as a bearer token, so the server can authenticate the caller. It says nothing about how the body is encoded. Cisco DNA Center does require authentication, but that header alone will not make the server interpret a JSON payload correctly, so it does not address the encoding problem described in the scenario.
- ✓
Content-Type: application/json
Why this is correct
The Content-Type header declares the media type of the entity body in the request, so setting it to application/json tells Cisco DNA Center to parse the create-site payload as JSON rather than form-encoded or plain text. Without it, the server may reject the request with 415 Unsupported Media Type or misinterpret the body, making this the correct header for the scenario.
- ✗
Accept: application/json
Why it's wrong here
The Accept header tells the server which media types the client is willing to receive in the response. It does not describe the format of the request body being sent, so setting it alone would leave the server guessing how to parse the create-site payload. While useful for negotiating response format, it does not satisfy the requirement to declare the encoding of the data being submitted.
- ✗
Content-Length: application/json
Why it's wrong here
Content-Length must contain the size of the body in bytes, not a media type. Supplying a media type string in this header would be malformed and could cause the server to misread or truncate the request body. It is not the mechanism for declaring payload format, so this option fails to solve the problem and would likely break the request outright.
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JA
Written and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed September 2026 · checked against the official Cisco exam blueprint
This 200-901 practice question is part of Courseiva's free Cisco certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the 200-901 exam.