Suppose we have an iron nail and an iron ball of same mass. When submerged in water, the iron ball may float but the nail always sinks. This is because

• Correct answer
  A

  buoyant force on the ball is larger than that of the nail due to their shapes
• B

  viscous force on the ball is higher
• C

  viscous force on the nail is higher
• D

  gravitational force affects the ball differently from the nail

Hence, the correct answer is option: 'A'.