53. My mom went to the grocery store. She forgot her purse
a. comma b. and c. or d. but e. because
The correct answer to complete the sentence is "b. and".
To determine the correct answer, we need to consider the context and the logic of the sentence. The sentence states that the speaker's mom went to the grocery store, but she forgot her purse. This indicates that both actions happened simultaneously; the mom went to the grocery store and, at the same time, forgot her purse.
To express this idea of two simultaneous actions, we use the conjunction "and". Option b, "and", is the correct answer because it connects the two actions and reflects their chronological relationship.