Answer : The correct option is, (A) Physical properties can be observed without changing the identity of the substance, while chemical properties can not.
Explanation :
Physical properties : It can be observed or measured without changing the chemical property of the substance.
In the physical property, no new compound or substance is formed only changes occur in the phase.
Chemical properties : It can be observed or measured by changing the chemical property of the substance.
In the chemical property, a new compound or substance is formed and no changes occurs in the phase.
Hence, the correct option is, (A)