Question

Why did bassanio choose lead casket

Answer 1

Bassanio know that all the glisters are not made of gold. So, he refused gold. He liked the silver coins where there are tween man and man. He called those coins as common drudge. He chosen the lead basket because he know if the outside of the basket not looks like good but the true worth lies inside it.  

Answer 2

In lead casket it was written 'Who chooses me must give and hazard all he has' .
Bassanio chose lead casket because he was love with Portia and was ready to make sacrifices for the woman he loved.The inscription on the lead casket seemed to reflect his love for her.