Passage: In March 1981, the USAF announced the Enhanced Tactical Fighter  program to procure a replacement for the F-111. The program was later renamed the Dual-Role Fighter (DRF) competition. The concept envisioned an aircraft capable of launching deep air interdiction missions without requiring additional support by fighter escort or jamming. General Dynamics submitted the F-16XL, while McDonnell Douglas submitted the F-15E. The Panavia Tornado was also a candidate, but since the aircraft lacked a credible air-superiority fighter capability, coupled with the fact that it is not American-made, it was not seriously considered.

Question: What did Douglas submit?
the F-15E