Statistics in singular sense includes:
A. Collection of data
B. Organisation of data
C. Statistical Methods
D. Both A and B

Hint: We first discuss the concept of Statistics in both plural and singular sense. We take examples to understand the concept of singular sense better.

Complete step-by-step solution:
The word Statistics is associated with the term state. Statistics is used as both a plural and singular noun.
In the plural sense, numerical data or statements of facts in connection with any field of human experience are called statistics.
On the other hand, the term Statistics, in a singular sense means the aggregate of scientific methods which deals with the collection, presentation, analysis and interpretation of numerical data. This singular sense of Statistics is used and contributed in various branches of Statistics.
For collection of data most of the statistical analysis is performed on the basis of collected data. The methods of data collection like primary and secondary, census and sampling etc. are related with data collection.
For organization of data after collecting data, systematic arrangement is essential. They are organized and presented in tables on the basis of rows and columns. This process is known as presentation of data.
The correct option is D.

Note: In a singular sense, it means the science of counting or science of average. This definition also has other features like analysis and interpretation. Science of statistics also includes the methods of collecting, organising, presenting, analysing and interpreting numerical facts and decisions are taken on their basis.