Translation:He said no.
~ています form indicates a continuous state of doing or being. You'll notice the translations here are "what was she sayING" vs. "he SAID no." Plain ~ます form would be translated as "says," as opppsed to the former two.
~ます indicates a habitual/regular doing ("I eat fruit") or indicates intent to do ("i will eat fruit"). It is better described as Imperfective Tense than Present, as it implies that the action is not in a state of completion, wherever in that process you may be.
~ています is a Stative Tense, indicating a present state of doing or being. Also better described this way than as a Present Tense. 食べています (I am eating) as opposed to 食べます (I eat), for example.
A better example would be 知っています (I am knowing) as opposed to 知ります(I know), where knowing something is seen more as a state of having knowledge than English's more encompassing knowing of something. To just say 知ります would indicate an imperfective state of coming to know something, or simply a habit of coming to know things on a regular basis, but once something is known, it changes to the stative tense of being known, as it can not be un-known.
....it can get a bit confusing, but that's why you should find a way to take a course from a teacher rather than relying on duo to get you by :)