In which of the following sampling methods, the sample is also known as an accidental sample and a haphazard sample?

The correct option is Convenience Sampling.

Detailed Explanation:
Convenience sampling is a non-probability sampling technique where the researcher selects participants who are easiest to reach, contact, or recruit. Because the selection is based purely on availability and accessibility rather than a systematic or random process, the resulting sample is often referred to as an accidental sample or a haphazard sample.

Here is a breakdown of why this term is used and why the other options do not fit:
1. Convenience Sampling (Accidental / Haphazard): Since the researcher chooses subjects who happen to be nearby or readily available (for example, interviewing shoppers at a local mall or surveying classmates), the encounters are "accidental" or "haphazard" in nature. There is no pre-planned structure to ensure representative diversity.
2. Purposive Sampling: Also known as judgmental or selective sampling, this method involves selecting participants based on specific characteristics or the researcher's professional judgment to meet a particular objective.
3. Quota Sampling: In this method, the population is segmented into mutually exclusive subgroups, and the researcher is given quotas to fill from these groups. While it is non-probability sampling, it is structured around quotas rather than being purely accidental.
4. Stratified Random Sampling: This is a probability sampling method where the population is divided into subgroups (strata) and participants are randomly selected from each stratum, ensuring statistical representation.