2.25 understand that energy requirements vary with activity levels, age and pregnancy

Different 'types' of people require different levels of energy, your energy requirements will depend on...

Your activity level
Active people need more energy than people who sit about all day, as they will be burning much more calories each day and therefore need more energy to burn them

Your age
Children and teenagers will need more energy than adults as they are still growing (and are generally more active)

Pregnancy
Pregnant women need more energy than non-pregnant women as they have to provide energy for not only themselves but also for their babies to develop