A single-gene trait that has two alleles and that shows a simple dominant-recessive pattern will result in a. one phenotype.
b. two phenotypes.
c. four phenotypes.
d. millions of phenotypes.​

A. One phenotype

sulfur dioxide

explanation: acid rain is caused by a chemical reaction that begins when compounds like sulfur dioxide and nitrogen oxides are released into the air. these substances can rise very high into the atmosphere, where they mix and react with water, oxygen, and other chemicals to form more acidic pollutants, known as acid rain.

the titanic would be the correct answer