The speed of light (c), gravitational constant (G) planck's constant (h) are taken as the fundamental units in a system. The dimensions of time in this new system should be,

a) G¹/²h¹/²c⁻⁵/²
b) G⁻⁵/²h¹/²c¹/²
c) G¹/²h¹/²c⁻³/²
d) G¹/²h¹/²c⁵/²