The Blood Group of parents (both father & mother) is A+. Their female child blood group is A-. Is this possible?

If the parents both carry the recessive gene form (allele) for the Rh gene then yes it is possible.

If dad was AA+- or Ao+- he could make a sperm cell that contained an A-. (possible sperm cells A+, A- in the first case & A+, A-, o+, o- in the second).

If mom also had either of the above genotypes she could produce an egg cell A- or o- and a baby with the phenotype (body) type A blood, Rh negative.

To set up the punnett squares:

dad AA+- with mom AA+-  (dad always goes on top of punnett suare)

A+     A-

A+

A-

you get a 1 in 4 chance of a AA-- (type A negative baby)

dad Ao+- with mom AA+-

A+     A-     o+     o-

A+

A-

you also get a 2 in 8 (1in4) chance of a type A negative child

dad Ao+- with mom Ao+-

A+     A-     o+     o-

A+

A-

o+

o-

you get a 3 of 16 chance of a type A negative child

(Even a type AB+- father or mother could produce sperm and egg cells capable of making a Type A negative child.)