Final answer:
Winter days are perceived as shorter due to fewer daylight hours, a result of the Earth's 23.5° axial tilt. While a calendar day is still 24 hours, the reduced daytime in winter leads to this common saying.
Step-by-step explanation:
When people say winter days are shorter than summer days, they are referring to the amount of daylight hours and not the actual 24-hour length of a calendar day. The correct answer to why winter days feel shorter is B) Daylight hours are shorter in winter due to the Earth's tilt. The 23.5° tilt of Earth's axis causes the Sun to be lower in the sky during winter, resulting in fewer daylight hours. At the winter solstice, for example, the Sun's rays have less time to heat the Earth because it's in the sky for fewer than 12 hours.Differentiating further, a solar day is based on the Earth's rotation relative to the Sun, which we use for everyday timekeeping. Meanwhile, a sidereal day is shorter and is defined by Earth's rotation relative to distant stars. Due to Earth's movement in its orbit around the Sun, a solar day is about 4 minutes longer than a sidereal day.Therefore, while all days measure the same in terms of hours, the perception of shorter days in winter is due to shorter periods of sunlight, a consequence of the Earth's axial tilt and the angled path of its orbit.