I will correct the mistakes in the sentences:
A. I thought I seen him in the yard.
Mistake! It should be:
A. I thought I saw him in the yard.
C. When had you saw him last?
Mistake! It should be:
C. When had/have you seen him last?
D. Mary sawed that man again yesterday.
Mistake! It should be:
D. Mary saw that man again yesterday.
So, options A, C and D have mistakes, but option D does not have a mistake in it!
Answer:
C. All the museum exhibits turn a bright neon color under a special kind of light
Explanation:
A foot<span> in </span>poetry<span> refers to the metrical </span>foot<span>. It is a unit of measure </span>used<span> to analyze the rhythm of a </span><span>poem</span>
I believe it is C, though I am not entirely sure. A compound sentence is two separate sentences combined with a conjunction, so I'm pretty sure that's correct.