The correct answer is Queen Gertrude is caught between her new husband and her son.
B is definitely incorrect because his father is dead so he cannot observe his conversation; C is incorrect because Gertrude believes Hamlet should blindly follow what Claudius has to say; D is incorrect because Hamlet hates Claudius.
This leaves us with sentence A - Gertrude has just lost her husband but she remarried immediately. Now, she is torn between her son whom she loves, and her new husband, who she feels she should obey.
