Option (A)This option says That F→ G is satisfiable means it can be true or false, also F is Satisfiable meaning it can be true, now does this mean that if both above conditions are true then G is also satisfiable?
No, If we take g as contradiction Then f alone can decide the value of F→ G , when f is true the implication is false since true → False is False and when F is False , the implication is true, False → Anything is true.
So even if F→ G is satisfiable and F is satisfiable G need not be satisfiable, it can be unsatisfiable/Contradiction
This way we can say option is isn’t true
Option (B) This statement can be understood in multiple ways, one way is to think of logical equivalence and equal sign, When we take negative on both sides we still end up with an equality.
another way is to take its formula : A↔ B means both are same/equal/equivalent/both true or false. Since their truth values will be same so negation will be same too, 0↔ 0 taking its negation 1 ↔ 1
So option B is true
Option (C) This a simple fact about implication, if antecedent is false then whatever is consequent the implication is true since false → anything is true
So option c is true
Option (D) This is another observation of implication, The only case in which implication is false is when q of p→ q is false and p is true, here if q is always true then p→ q will always be true
This way option B,C,D are true