The merits of Census method include __________.
A.It is accurate
B.It rules out errors of sampling
C.It is reliable
D.All of the above

Hint: First we need to know that meaning of census method, where a major merit of this method is the accuracy that is gotten by consulting each and every unit of the population, before drawing the results of the research.

Complete step-by-step answer:
We are given that the method is Census.
We know that the process used in the census method includes the statistical compilation of all units or members of the target population under the survey. So, in this case we relate the population to the entire set of observations connected to a particular study.
For example, if employees of an office have to give feedback on the staff faculty, the former will be held as the population of that study.
When we search for the advantages of census method, we need to remember two points:
1) Intensive nature of study: When we have to go for the in-depth information, which is related to an issue is covered. It will help us in all-inclusive understanding.
For example, in population census, apart from counting a number of people, other parameters are also considered, like age, sex, marital status etc.
2) Accuracy and reliability of result: We know that the results are more reliable and accurate owing to the vast number of items that are taken into account.
So, a major merit of this method is the accuracy that is gotten by consulting each and every unit of the population, before drawing the results of the research. 
So, from the above two points and the given options, we have found that it does not rule out errors of sampling and reliability.
Therefore, the merits of the census method includes it is accurate.
Hence, option A is correct.

Note: We know that when the data is collected from the entire population it is called census method. In this case, each and every unit of population is studied. It is most commonly used by the Government in connection with the national population, housing/agriculture census, preparation of voter's list, income tax assessment etc.