It means to not think about a certain thing or objective, but to think freely.
The answer is B because her prompt is very clear and well said being related to Thomas Edison
C because it is saying the moon sang to the clouds and the moon cannot talk so it’s a form of personification.
I'm not going to write the letter for your 45 year-old self obviously but start by saying "How has the journey been so far". Consider all the factors like having your children being the age you are now. At 45 you may be a lot more smart, definitely more wealthy. Wish yourself luck no matter how blank the future may be, etc.