Not A, or D as they should be said by Maria, (A, because it IS her opinion, and D, because why would Tim want Maria to believe him when it is her statement?)
B sounds a little too dismissive, so I think C is the most appropriate answer, given the subject of using robots in place of humans for dangerous job
Although, I have never heard of a non-dismissive "That sounds interesting", it could just be the folks I'm around. Maybe it is just their tone that makes it some "Interesting, anyway,"
Well, she said context matters, and before this it is stated that they both are talking about Robots, which means B is kinda brushing off while A sounds like a building statement
Question 24: Maria and Tim are talking about modern Robot
Maria:"I believe that modern robots will be more intelligent and replace humans in many dangerous jobs."
Tim:"[...]"
A. That's just what I think of course
B. That sounds interesting
C. That's a good idea
D. Why not? Believe me!