Need explaination for 1) and 4)th options
For option 1
In chlorobenzene, there is resonance involved which forms a partial double bond character in the carbon-chlorine bond by reducing the net dipole moment.
In cyclohexyl chloride there is no such mechanism
Theoretically we see dipole moment according to the electronegativity difference but actually in CO the more dominating factor is coordinate bond which results that dipole is formed due to a complete + ve and - ve charge instead of just partial +ve and -ve charge due to electronegativity difference .
And hence experimental > theoretical