Identifying O2 sensors - End of module question

One question asked how to identify O2 sensors....after missing the question multiple times, the answer was number of wires and colour. Colour was never discussed in this module, and I feel the right answer should have been number of wires and shape. I am not sure if this question and answer is correct.

Apologies, I'll look into that and get it corrected. Thanks for bringing it to my attention.