Strong emotions help form stronger memories primarily because they create stronger encoding of memories. When we experience powerful emotions, our brain releases neurotransmitters and hormones, such as adrenaline, which enhance our ability to encode and retrieve memories. This heightened emotional state makes certain experiences more salient and memorable, increasing the likelihood of recalling those memories in the future.
While it is true that strong emotions can also capture our attention and may influence our perception of facts, the key mechanism through which emotions enhance memory formation is through improved encoding and consolidation processes in the brain. Therefore, the statement "They create stronger encoding of memories" is the most accurate explanation for why strong emotions are associated with stronger memories.