单选题 Which of the following, if true, would most seriously undermine the validity of the model of star formation that is presented in the passage?

• (A) A star is discovered that emits lower levels of trace ions than those discovered by x-rays of our galaxy's sun.
• (B) A section of the universe is discovered to lack both stars and any sort of interstellar medium.
• (C) A galaxy is discovered with a negative rate of star formation.
• (D) In one corner of the galaxy, coronal gas is discovered to rarify as it becomes cooler.
• (E) A superbubble is found of equal mass to the galaxy surrounding it.