In IELTS Speaking Part 1, the examiner is mainly testing you for two things: i) everyday vocabulary and, ii) basic grammar.
For almost every answer, you should give a two-part answer: First, a direct answer to the question and then add more information.
A 'direct answer' does not mean the same as 'an immediate answer' – a 'direct answer' means 'not an indirect answer'. Indirect answers lower your coherence score. Here's an example of an indirect answer:
Question: "Do you work or are you a student?"
Answer: "Oh, I've been working for five years."
That answer does tell the examiner that you are working but it does so indirectly. The question asks you to choose between "A" and "B" and, in order to answer directly, you should first choose between A and B and then add some suitable extra information. So, a more suitable answer is, "I'm working. In fact, I've been working for five years."