Final answer:
The element in RNA pol II promoters that overlaps the transcription startpoint and is rich in pyrimidines is the Initiator.
Step-by-step explanation:
In RNA polymerase II promoters, the element that overlaps the startpoint for transcription and is rich in pyrimidines (C or T) is known as the Initiator (Inr). The Initiator is a core promoter element that is present in some genes right at the transcription start site and is characterized by having a consensus sequence which is rich in cytosine (C) and thymine (T). It plays a critical role in the precise initiation of transcription by RNA polymerase II and is distinct from other regulatory elements such as enhancers, silencers, and the TATA box.