Which type of disenfranchisement was used in an effort to prevent people who could not read or write from voting?

identification requirements
grandfather clauses
poll taxes
literacy tests

literacy tests were used in an effort to prevent people who could not read or write from voting.

Literacy tests

Explanation:

"[...]the most formidable voting barrier put into the state constitution was the literacy test. It required a person seeking to register to vote to read a section of the state constitution and explain it to the county clerk who processed voter registrations. This clerk, who was always white, decided whether a citizen was literate or not.

The literacy test did not just exclude the 60 percent of voting-age black men (most of them ex-slaves) who could not read. It excluded almost all black men, because the clerk would select complicated technical passages for them to interpret. By contrast, the clerk would pass whites by picking simple sentences in the state constitution for them to explain."

Reference: Costly, Andrew. “Race and Voting - Constitutional Rights Foundation.” Race and Voting - Constitutional Rights Foundation, 2019

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