Correct option is B
Explanation-
Analyzing Each Statement-
A. It describes species relationships and is therefore the best method to describe a new species - INCORRECT
While UPGMA shows relationships, it assumes equal evolutionary rates (molecular clock), which is not always true. So, it is not the best method to describe new species — other methods like Maximum Likelihood or Bayesian approaches are more reliable for that.
B. It is a method of hierarchical clustering - CORRECT
UPGMA is a hierarchical clustering method used in phylogenetics to construct rooted trees (dendrograms) based on genetic distance or similarity.
C. The raw data is a similarity matrix and the initial tree is rooted - CORRECT
UPGMA uses a distance or similarity matrix (often derived from sequence data). The resulting tree is rooted because UPGMA assumes a molecular clock — that is, all lineages evolve at a constant rate.
D. It permits lineages with largely different branch lengths and corrections for multiple substitutions - INCORRECT
UPGMA does not handle varying branch lengths well. It assumes ultrametricity (equal distance from root to all tips) and does not correct for multiple substitutions — this is a limitation.
Final Answer:
Statements B and C are correct
Correct option is b - B and C
