GRE Reading Comprehension: Princeton-GRE阅读Princeton - F0QFX1M124S911LPC$

According to the passage, a standard candle may not provide an accurate measure of distance if A. the galaxy being measured is moving too quickly B. interstellar dust makes the object measured appear dimmer than it really is C. if the galaxy being measured has a local component of measurement D. the particles being measured do not completely accord with a linear motion E. the galaxies being measured move at different speeds