Pls help me with this question

The answer is a.  i hope this

Amicroscope, because these cells are so small that you would not be able to see them, or what they attack without it.

I'm having some difficulty seeing the diagram clearly.but the question says there's a net inward force on the object.so we know right away,  from newton's 2nd law of motion, thatthat baby is accelerating.  it doesn't even matter which way thenet force is pointing.  if there's any net force, then either theobject's speed or else its direction must be changing.

D. a  bar magnet with its south pole on the left