Answer: a)Implicit data type conversion is performed when you mix values of different data types in an expression.
Explanation: Implicit datatype conversion is the conversion mechanism in which the operand persisting the lower data type is changed into the higher data type for an expression.This process takes place automatically to maintain the compatibility of datatype in an expression.
Other options are false because every datatype is not changed to other until the higher data type is found.There is no priority order from high to low for conversion. Implicit conversion is done by compiler automatically. Thus, the true statement is option(a).