A liquid whose coefficient of volume expansion is ${\gamma }_r$ , completely fills a sealed metal tank, at negligible pressure. The coefficient of linear expansion of the metal is $\alpha$  and the compressibility of the liquid is k. If the temperature of the system is increased by t. The pressure of the liquid will be 

• A

  ${\gamma }_r\frac{t}{k}$

• B

  $\frac{t}{k}({\gamma }_r-3\alpha )$

• C

  $tk({\gamma }_r-3\alpha )$

• D

  $\frac{t}{k}({\gamma }_r-\alpha )$