What term describes when participants drop out of a longitudinal study?

According to the chapter Flash in the Panabout flashbulb memories, how did the researchers evaluate

how much information participants reported in response to the open-ended question that asked them to describe the circumstances in which they first learned about the 9/11 attacks? (a) they timed how long each participant spent writing his/her response (b) they asked each participant a follow up question about how long they spent writing their response (c) they counted how many words participants wrote in response to the question (d) they measured how much space on the page each participant took up in writing their response

One of the best predictors of bereavement adjustment is

a. suddenness of the death b. age of the deceased c. age of the survivor d. health habits of the deceased e. character of the relationship between the deceased and the bereaved