Here's the part I'm referencing:

HOLT: Mr. Trump, this year Secretary Clinton became the first woman nominated for president by a major party. Earlier this month, you said she doesn't have, quote, "a presidential look." She's standing here right now. What did you mean by that?

TRUMP: She doesn't have the look. She doesn't have the stamina. I said she doesn't have the stamina. And I don't believe she does have the stamina. To be president of this country, you need tremendous stamina.

HOLT: The quote was, "I just don't think she has the presidential look."

TRUMP: You have -- wait a minute. Wait a minute, Lester. You asked me a question. Did you ask me a question?

You have to be able to negotiate our trade deals. You have to be able to negotiate,that's right, with Japan, with Saudi Arabia. I mean, can you imagine, we're defending Saudi Arabia? And with all of the money they have, we're defending them, and they're not paying? All you have to do is speak to them. Wait. You have so many different things you have to be able to do, and I don't believe that Hillary has the stamina.

The implication here is obvious. "These two countries have a history of subjugating women, how can we appear strong with a woman at the helm?" Especially with the entire question framed. When Donald was asked what he means by "Presidential Look" he lies, says he said "She doesn't have the stamina", then when corrected with his own quote the dog-whistle sexism creeps out, on a national stage, with one of the most distinguished women of our time standing opposite him. When he mentions Saudi Arabia, he then changes the subject, and brings it back to stamina, even though he never mentioned one thing that required stamina.