Select the three major classifications of galaxies. (Select all that apply.)irregularclustersphericalregularquasarspiralelliptical

Step 1: Break Down the Problem

We need to identify the three major classifications of galaxies from the given options.

Step 2: Relevant Concepts

The major classifications of galaxies are typically recognized as:

1. Elliptical Galaxies - These have an ellipsoidal shape and a smooth, featureless brightness profile.
2. Spiral Galaxies - Characterized by a flat, rotating disk containing stars, gas, and dust, as well as a central concentration of stars known as the bulge.
3. Irregular Galaxies - These galaxies do not fit into the traditional categories of elliptical or spiral galaxies and often have an irregular shape.

Step 3: Analyze and Detail

From the options provided:

• Irregular is a classification of galaxies.
• Elliptical is also a classification.
• Spiral is another classification.
• Clusters refer to groups of galaxies and are not a classification of a single galaxy.
• Spherical is not a standard classification in astronomy.
• Quasars are extremely luminous active galactic nuclei and are not classified as galaxies themselves.

Step 4: Verify and Summarize

The three major classifications that fit the criteria are spiral, elliptical, and irregular.

Final Answer

The three major classifications of galaxies are:

1. Spiral
2. Elliptical
3. Irregular