Ill give 20 points plz help and explain

The correct answer is a)

Because if you would just put everything in a equation, it would look like this:

and if you would just add that together you would recieve .

< coa = 150 ( given)

as ba and bc are tangents

so oc and oa is perpendicular to cb and ab respectively because in circle normal passes through centre

so in quadrilateral oabc

< coa + < oab + < ocb + < abc = 360

150 +90+90 + < abc = 360

330 + < abc = 360

< abc = 360 -330 = 30

so < abc = 30

⭐dhruv⭐

fyuh

step-by-step explanation:

gvfvhv