Read the following statements :
$\mathrm{A}$. When small temperature difference between a liquid and its surrounding is doubled the rate of loss of heat of the liquid becomes twice.

$\mathrm{B}$. Two bodies $P$ and $Q$ having equal surface areas are maintained at temperature $10°\mathrm{C}$ and $20°\mathrm{C}$. The thermal radiation emitted in a given time by $P$ and $Q$ are in the ratio $1:1.15$

$\mathrm{C}$. A carnot Engine working between $100 \mathrm{K}$ and $400 \mathrm{K}$ has an efficiency of $75\%$

$\mathrm{D}$. When small temperature difference between a liquid and its surrounding is quadrupled, the rate of loss of heat of the liquid becomes twice.

Choose the correct answer from the options given below :

• Correct answer
  A

  $\mathrm{A},\mathrm{B},\mathrm{C}$ only
• B

  $\mathrm{A},\mathrm{B}$ only
• C

  $\mathrm{A},\mathrm{C}$ only
• D

  $\mathrm{B},\mathrm{C},\mathrm{D}$ only

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