Which of the following statements are true?
i. each white blood cell contains millions of hemoglobin molecules.
ii. in a sample of blood, there are more red blood cells than white blood cells.
iii. hiv destroys red blood cells.
iv. all blood cells come from one pool of stem cells.
a. ii and iv only
b. i and iv only
c. ii and iii only
d. i, iii, and iv only
e. i, ii, and iv only

answer: national resource conservation services

national resource conservation services is the us. based approach that provides technical and financial assistance for natural resource management. nrcs society in conservation of resources by involving in activities like farmland protection, flood prevention, watershed protection, urban conservation, conserves economic and environmental conditions. it conducts soil surveys and implements the policy of natural resources management on the society.

a symbiotic relationship with the mitochondria