In a heated debate in biogeography, the field is divided between dispersalists and vicariancists. __ there are those who argue that dispersal is the most crucial determining factor in a species'distribution, and those who insist that vicariance (separation due to geographic barriers) is Biogeographer Isabel Sanmartin counts herself among neither. Which choice completes the text with the most logical transition? A. Furthermore B. By contrast C. Similarly D. That is

## Step 1<br />The problem is asking us to choose the most logical transition word for the given text. The text discusses two opposing views in biogeography: dispersalists and vicariancists. The text then introduces Biogeographer Isabel Sanmartin, who doesn't align with either of these views.<br />## Step 2<br />We need to choose a transition word that best fits the context of the text. The transition word should indicate a contrast or a different viewpoint, as the text is introducing a new perspective that is different from the two previously mentioned views.<br />## Step 3<br />Looking at the options, "By contrast" is the most suitable transition word. It indicates a contrast or a different viewpoint, which is exactly what we need in this context.