True about cross section study-

Ans. is 'd' i.e., All of the above Cross - sectional studieso Cross sectional study is the simplest form of an observational study.o It is also known as prevalence study.o It is based on a single examination of a cross - section of population at one point of timeo Results of this examination can be projected on the whole populationo Cross-sectional study tells about the distribution of a disease rather than its etiology.o Cross-sectional studies can be thought of as providing a snapshot of the frequency and characteristic of a disease in a population at a particular point in timeo Cross-sectional study is more useful for chronic diseaseo As population is studied at once, no follow-up is required.