Michael Can Buy Either Pizzas or Submarine Sandwiches

Multiple Choice

Michael can buy either pizzas or submarine sandwiches. If the prices of pizzas and submarine sandwiches double and Michael's money income triples, we can conclude that Michael's budget constraint will

A) shift in but remain parallel to the old one.
B) shift out but remain parallel to the old one.
C) swivel in so that the slope of the budget constraint is doubled.
D) remain unchanged.