Most adults struggle to recall events from their first...

Câu hỏi: Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks.
Most adults struggle to recall events from their first few years of life and now scientists have identified exactly when these childhood memories are lost forever. A new study into childhood amnesia has found that it tends to take (33) _____ around the age of seven. The rapid decline of memories persisting while children are five and six is owing to the change in the way memories are formed.
Before the age of seven, children tend to have an (34) ________ form of recall with no sense of time and place in their memories. In older children, however, the early recollected events tend to be more adult like in their content and the way they are formed. Faster rate of forgetting in children and higher turnover of memories means early memories are less likely to survive. (35) ________, memories of younger children tend to lack autobiographical narrative leading to a process known as retrieval induced forgetting (36) ______ the action of remembering causes other information to be forgotten. Consequently, if childhood memories can survive into the ninth or tenth year of life, they may stay a chance of (37) _____ it into adulthood.
The word or phrase which best fits the gap (33) is...
A. affect
B. effective
C. effect
D. effectively