Match the following:

Metal	Uses
$1$. Sodium	$a$. For preparing springs
$2$. Beryllium-copper	$b$. In treatment of cancer
$3$. Radium	$c$. In preparation of aeroplanes
$4$. Magnesium-aluminium	$d$. In color industries

• A
  $1-d, 2-a, 3-b, 4-c$
• B
  $1-a, 2-b, 3-c, 4-d$
• C
  $1-b, 2-c, 3-d, 4-a$
• D
  $1-c, 2-d, 3-a, 4-b$