The correct answer is "influence". "Effect" isn't the right word here, cause you can't "effect"on something, "effect" is the result. Better said "effect" is the result of the "influence". Here "The family has a lifelong influence on his or her personality.". His/her personality can be the effect of the influence he/she got from the familly. I hope it helps!

That'd be "influence". The reason? - Effect is a change which is a result of an action Or other cause. - Influence is the capacity to have an effect on the character, development, or behaviour of someone or something, or the effect itself. (Something that happens over a longer period with long-term consequences) I hope this helps.

"effect" is a short-term thing so you must choose "influence"

I would say "influence" because it is something that has happened over a period of time. Greetings! Teacher Charles, https://www.italki.com/teacher/5853252

effect