The property which is not true about Fluorine is,

The correct order of bond dissociation enthalpy of halogens is:

Which of the following statements regarding the properties of halogens are correct?
$(a)$ Due to small size and strong inter-electronic repulsion,the electron gain enthalpy of fluorine is less negative than that of chlorine.
$(b)$ Iodine has a different physical state and colour compared to other members of the group.
$(c)$ Fluorine does not show a positive oxidation state.
$(d)$ In $X_{2(g)} + H_2O(l) \rightarrow HX(aq) + HOX(aq)$ (where $X = Cl$ or $Br$).

Mercury on heating with aqua-regia gives

What is the color of the solution when iodine is dissolved in $CCl_4$?

Hypo is used in photography for