When considering time management techniques, it is important to remember that a. the more techniques used, the better off you will be b. you have to try strategies that don’t make sense for your type of work c. not all techniques work well for all people in all situations d. each strategy can work for everyone

The correct answer is c. 

Everyone will be different, and will have different problems and objectives throughout the day, so there is no one time management technique that fits everybody. 

Option a is incorrect because the quality of the technique over the quantity is more important. 
Option b is incorrect because you want the techniques to make sense for your type of work. 
Option d is incorrect because it's the opposite of the actual answer. 

C. Not all techniques work well for all people in all situations.

If we look back in history, there have been some famous people who offered their techniques on time management.

Benjamin Franklin, for instance, rigorously kept a log of all his daily activities.

Letts of London is a famous maker of calendars and appointment books -- which was begun by John Letts way back in 1796, when he founded a stationery company, and in the early 1800s was the first to introduce a commercial diary / appointment book for merchants.

President Dwight Eisenhower had a system for managing time and tasks.  He classified items according to their urgency and importance.  Urgent and important items were dealt with immediately.  Urgent but unimportant items were assigned to staff members to handle.  Important, but not urgent, items were scheduled onto a calendar for handling at an appropriate time.  Items that were neither urgent nor important were to be reduced or eliminated from his schedule.