When, in Ida B. Wells's reporting, white men in the 1890s said that they had to lynch black men to teach them a lesson, for what reason did they claim such a lesson was deserved

Incomplete question. The options:

A. Black Southerners were not acting subordinate to whites.

B. Too many black Southerners were graduating from high school.

C. Black women were refusing the advances of white men.

D. Black men were running for local political office.

A. Black Southerners were not acting subordinate to whites.

Explanation:

Sadly, because of the ingrained racial discrimination at the time, "Whites" felt that "Blacks" were subordinates. In other words, they ("the Whites") wanted to exercise headship over the "Blacks".

This wrong reasoning was highlighted in B. Wells's own words,

"The Negroes are getting too independent," they say "we must teach them a lesson."

What lesson? The lesson of subordination. "Kill the leaders and it will cow the Negro who dares to shoot a white man, even in self-defense."