In a combination tournament, different formats of matches are combined to create an exciting and varied competition. The popular combinations in this type of tournament are:

a) Knockout come knockout:
This format involves a knockout round followed by another knockout round. In the first round, teams or individuals compete against each other, and the winners proceed to the next round while the losers are eliminated. The winners of the second round then face off in the final, determining the ultimate winner of the tournament.

b) League cum League:
In this format, multiple leagues are conducted, where teams or individuals compete against each other in a round-robin format. Each team plays against every other team, and points are awarded for wins, draws, or losses. The team with the highest number of points at the end of the league stage is declared the winner.

c) League cum Knockout:
This format combines a league stage with a knockout stage. Initially, teams or individuals compete against each other in a league format, earning points based on their performance. The top teams or individuals from the league stage then progress to the knockout stage, where they compete in knockout matches to determine the champion.

d) All the above:
The correct answer is option 'D' because all of the mentioned combinations (knockout come knockout, league cum league, and league cum knockout) are popular in combination tournaments. These formats provide different types of challenges and excitement for the participants and spectators.

In a combination tournament, the choice of format depends on various factors such as the number of participants, available resources, time constraints, and desired level of competitiveness. Each format offers its own advantages and appeals to different preferences. Some participants may prefer the intense pressure of knockout matches, while others may enjoy the consistency and strategy involved in league formats. Combining these formats in a single tournament allows for a diverse and engaging competition.

Overall, the popularity of these combinations lies in their ability to offer a mix of excitement, skill, and strategy. The different formats cater to different aspects of the game and provide participants with a variety of challenges. By incorporating both knockout and league stages, combination tournaments ensure that participants have the opportunity to showcase their abilities in different settings and formats.