The segment that contains a grammatical error is Option D.

The correct phrase is “put forth” or “presented” when referring to proposals in a meeting. The phrase “put on” is not typically used in this context. Hence, the segment “put on at the meeting,” contains a grammatical error. The corrected phrase should be “put forth at the meeting,” or “presented at the meeting,”. So, the corrected sentence would be:

“Several proposals were put forth at the meeting, but none was appealing enough.” or “Several proposals were presented at the meeting, but none was appealing enough.”