I'm confused, is it A or D?

It is D.

Step-by-step explanation:

Remove parentheses: x + 3 > 10

Subtract 3 from both sides: x > 10 - 3

Simplify 10 - 3 to 7: x > 7

D. x>7

Step-by-step explanation:

Multiply - and -3

x+3>10

Subtract 3 on both sides

x>7

(Remember you can only switch the symbol if you divide or multiply by negative it does not apply on addition or subtraction)

Hope this helps!