Gary and Gail had their only child at 45, a bit later than most. Their son is now fifteen and there is a large gap between what Gary and Gail had expected for themselves and where their son needs attention. Overall, the communication problem here results from:
Explanation
Answer - B - Gary and Gail are now nearing 60, needing to look back on their life thus far with a sense of achievement and accomplishment, while their son looks forward to a lot of his life, looking to learn, build, make mistakes, and move forward. While not impossible, the life stages can prove to be a challenge for all involved.