Question 24. The twins are so alike: I cannot tell one from the other.
A. different
B. similar
C. changeable
D. confident

The word "alike" is closest in meaning to "similar."

Question 25. Scientists want to find out if there is, or has ever been, life on Mars. They are planning to send people there.
A. get some information
B. make a discovery
C. find plants and animals
D. carry out experiments

The phrase "find out" is closest in meaning to "get some information."