Assertion (A): Chloroplast has 70S ribosome.
Reason (R): They are descendants of bacteria.
Both A and R are true and R is the correct explanation of A.
Both A and R are true but R is not the correct explanation of A.
A is true but R is false.
A is false but R is true
Two subunits of the 30S and 50S ribosomes combine to form the 70S ribosome. The explanation for this is that chloroplast is a descendant of bacteria. As a result, the 70S ribosome may be found in bacterial cells, mitochondria, and chloroplasts. Hence, option 1 is the correct answer.
Explanation for the incorrect options :
Option 2 is incorrect because the reason is correctly explaining the assertion.
Option 3 is incorrect because chloroplasts are one of several types of organelles found in plant cells. Endosymbiotic cyanobacteria are thought to have developed into them. Hence reason is true.
Option 4 is incorrect because plant cells include three types of ribosomes: 80 S ribosomes in the cytoplasm, 70 S-like ribosomes in the chloroplasts, and mitochondrial ribosomes. Hence assertion is true.