Which finding from Mulder and Spellman's study, if true, would most d… | Verbal SAT Question

Port Clarence Indian paintbrush (Castilleja caudata) plants are native to Alaska, where the harsh boreal conditions historically impeded potential invasive species. In recent decades, however, bird vetch (Vicia cracca) plants have established themselves in Alaska. Studies have suggested that increasingly warm spring temperatures benefit invasive plant species more than native plant species, but no such studies have focused on boreal ecosystems despite similar temperature changes occurring there. To fill this gap, biologists Christa Mulder and Katie Spellman tracked C. caudata and V. cracca, along with other native and invasive species, over several years.

Which finding from Mulder and Spellman’s study, if true, would most directly support the claim that plant species in boreal ecosystems may not exhibit the pattern seen in studies of plant species in other types of ecosystems?

Although C. caudata and V. cracca tended to produce leaves at about the same time in years with historically typical spring temperatures, V. cracca produced leaves sooner than C. caudata did in years with relatively high spring temperatures.

Although C. caudata and V. cracca both tended to produce more leaves in years with relatively high spring temperatures than in years with historically typical spring temperatures, V. cracca showed a greater increase than C. caudata did.

Although C. caudata and V. cracca tended to produce initial leaves at different times, the size of that difference did not vary from year to year despite substantial interannual increases in spring temperatures.

Although C. caudata tended to produce fewer leaves per year than V. cracca did, interannual variations in spring temperatures during the study were within the historically typical range.