Why does Giles Corey say that his wife has been reading strange books?

Giles Corey claims that his wife has been reading strange books as part of his suspicion that she is involved in witchcraft. This reflects the broader context of paranoia and fear regarding the witch trials in Salem, where any unusual behavior or interests could lead to accusations and social ostracism.

In the play, Giles is confused and worried about the newfound interest his wife has in reading, which is something he does not understand and associates with the supernatural. His concern arises from the societal climate where unconventional activities, especially those related to women, are often seen as threatening.

The other options do not align with Giles's motivations. Protecting her reputation would likely lead him to deny such behavior rather than accuse her, showing outright concern rather than direct accusation. Expressing curiosity about her interests could suggest a level of understanding and acceptance that is inconsistent with his portrayal in the play. Trying to assist her academically is highly unlikely in the context of the play, given the historical backdrop and Giles's character, who is depicted as more practical than scholarly. Thus, accusing her based on the reading of strange books is deeply rooted in the fear and suspicion characterizing the Salem witch trials.