A man has a large inversion on one of his chromosomes. How might this impact his offspring?

The inversion can lead to dominant or recessive mutation which could cause phenotype abnormalities.

Explanation:

Inversion is a chromosomal mutation that changes the sequence of the chromosome due to rotation of the sequence to 180 degrees. This rotated sequence is thus inverted and then again joined to the chromosome.

If the inversion takes place in the sequence which determines the important characters in the organism then it could lead to the dominant or the recessive mutations in the organisms which could lead to severe abnormalities.

Thus, severe phenotype abnormalities are correct.