Testifying Wednesday before a House Appropriations subcommittee, Education Secretary Betsy DeVos refused to say whether she would pull federal funding from a state that allows schools to discriminate against LGBT students.

Massachusetts Representative Katherine Clark, a Democrat, repeatedly asked DeVos where she would draw the line.

“You talk a lot about the flexibility of states as being preeminent,” Clark stated. “So, I want to go back to Indiana, to Bloomington in particular, and look at the Light House Christian Academy. The Light House Christian Academy currently receives over $665,000 in state vouchers for students to attend their school.”

Clark noted that the school denies admission to students from LGBT households.

“If Indiana applies for this federal funding, will you stand up that this school be open to all students?” Clark asked. “Is there a line for you on state flexibility? … Would you in this case say, 'We are going to overrule. You cannot discriminate whether it be on sexual orientation, race, special needs in our voucher programs.' Will that be a guarantee for our students?”

“For states who have programs that allow for parents to make choices, they set up the rules around that,” answered DeVos, a vocal proponent of voucher programs.

“The bottom line is we believe that parents are best equipped to make choices for their children's schooling and education decisions. States and local communities are best equipped to make these decisions and framework,” she added.

Clark said that she was “shocked” that DeVos could not “come up with one example of discrimination that you would stand up for students.”

Critics of voucher programs say they deplete public schools of valuable resources and mostly benefit religiously-affiliated schools.

(Related: Trump's pick for secretary of education is Betsy DeVos, a gay marriage foe.)