Answer: The correct statements are
The GCF of the coefficients is correct.
The variable c is not common to all terms, so a power of c should not have been factored out.
David applied the distributive property.
Step-by-step explanation:
GCF = Greatest common factor
1) GCF of coefficients : (80,32,48)
80 = 2 × 2 × 2 × 2 × 5
32 = 2 × 2 × 2 × 2 × 2
48 = 2 × 2 × 2 × 2 × 3
GCF of coefficients : (80,32,48) is 16.
2) GCF of variables :(
)
= b × b × b × b
= b × b
=b × b × b × b
GCF of variables :(
) is 
3) GCF of
and c: c is not the GCF of the polynomial. The variable c is not common to all terms, so a power of c should not have been factored out.
4) 
David applied the distributive property.