The BEST estimate for the capacity of a bath tub is option B)-50 gallons
50 fluid ounces is a very smaller unit so it cannot be true.
50 cups is also small as compared to a standard bath tub that can hold almost 60-80 gallons of water.
50 pints is almost 6.25 gallons which is also very less amount of water as compared to the bath tub.
Hence, option B is correct estimate.
