Question

Question was provided via image upload.

Explanation:

First Question (The Milky Way galaxy is NOT):

The Milky Way is a spiral galaxy (not irregular), contains 200 - 400 billion stars, and is part of the Local Group. So the incorrect statement is it being an irregular galaxy.

• Option 1: Rotation of stars around Milky Way relates to dark matter's gravitational effect (to explain galaxy rotation curves), but the best fit here is the Wilkinson Microwave Anisotropy Probe (WMAP) data showing temperature variations linked to both regular and dark matter.
• Option 2: Oscillating action of universe is not a reason for matter types.
• Option 3: Steady - state theory is not about regular/dark matter distinction.
• Option 4: WMAP's cosmic radiation temperature variations support the existence of both regular and dark matter to explain the universe's structure and evolution.

Answer:

A. an irregular galaxy

Second Question (Why do some scientists believe...):