Answer:
The weight in x weeks of a puppy that gains 4 pounds per week if its starting weight is 16 pounds
Step-by-step explanation;
Let us analyze the option one after the other
1. "The amount an employee who makes $9.50 per hour earns in h hours"
This represents a proportional relationship, because for the more the employee works the more he earns
2. "The cost of purchasing p pounds of bananas for $0.36 per pound"
This represents a proportional relationship, because the more the pound the greater the cost
3. "The weight in x weeks of a puppy that gains 4 pounds per week if its starting weight is 16 pounds"
This is not because there was an existing 16 pounds, although it will get to a point where the relationship becomes a proportional relationship.
4. "The number of gallons of water in x barrels with 33 gallons of water in each barrel"
This is a proportional relation, because more barrels will contain more gallons of water.