What makes potassium hydroxide a deliquescent substance?

State one relevant observation for of the following:

Anhydrous calcium chloride is exposed to air for some time.

Give a suitable chemical term for 

The process in which a substance absorbs moisture from the atmospheric air to become moist and ultimately dissolves in the absorbed water.

Select the correct answer from A, B, C, D and E

A. Nitroso iron [II] sulphate

B. Iron [III] chloride

C. Chromium sulphate

D. Lead chloride

E. Sodium chloride

(i) A deliquescent compound

(ii) A compound soluble in hot water but insoluble in cold water.

(iii) A compound which in the aqueous solution state, is neutral in nature.

Write two example of deliquescent substance.

From the list of salts — $\mathrm{AgCl}, {\mathrm{MgCl}}_2, {\mathrm{NaHSO}}_4, {\mathrm{PbCO}}_3, {\mathrm{ZnCO}}_3, {\mathrm{KNO}}_3, \mathrm{Ca}{\left({\mathrm{NO}}_3\right)}_2$, choose the salt that most appropriately fits the description given below:

a deliquescent salt 

From the given compounds:

${\mathrm{MgSO}}_4.7{\mathrm{H}}_2\mathrm{O}, {\mathrm{FeCl}}_3, \mathrm{Conc}. {\mathrm{H}}_2{\mathrm{SO}}_4, {\mathrm{NaKCO}}_3, \mathrm{Pb}\left(\mathrm{OH}\right)\mathrm{Cl}$

Write the appropriate one: Deliquescent substance.