Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that best combines each pair of sentences in the following questions from 45 to 46.

His academic record at high school was poor. He failed to apply to that prestigious institution. 

A. The academic record at high school was poor because he didn't apply to that prestigious institution

B. His academic record at high school was poor as a result of his failure to apply to that pression institution

C. His academic record at high school was poor; as a result, he failed to apply to that prestigious 

D. Failing to apply to that prestigious institution, his academic record at high school was poor. 

Dãy gồm các ion có thể cùng tồn tại trong một dung dịch là

A.  Ca²⁺, Cl^-, Na⁺, CO₃^2-.      

B.  K⁺, Ba²⁺, OH^-, Cl^-

C. Al³⁺, SO₄^2-, Cl^-, Ba²⁺.

D. Na⁺, OH^-, HCO₃^-, K⁺.

Để phân biệt dung dịch AlCl₃ và dung dịch KCl ta dùng dung dịch

A. HCl.

B. H₂SO₄

C. NaNO₃

D. NaOH