| I: | Primary succession is faster than the secondary succession |
| II: | Both hydrarch and xerarch successions lead to mesic conditions |
| III: | Rooted submerged plants are pioneers in primary hydrarch succession |
| I. | Pioneers in primary xerarch succession are lichens |
| II. | Pioneers in primary hydrarch succession are phytoplanktons |
| III. | Secondary succession is slower than primary succession |
| I. | The change in communities during ecological succession is orderly and sequential, parallel with the changes in the physical environment. |
| II. | Secondary succession is faster than primary succession. |
| III. | Usually, lichens are pioneer species during primary xerarch succession. |
| 1. | Only I |
| 2. | Only II |
| 3. | Both I and III |
| 4. | I, II and III |
| Column I | Column II | ||
| A. | Primary Succession | P. | Takes place in dry areas and the series progress from xeric to mesic conditions |
| B. | Secondary Succession | Q. | Occurs in areas like newly cooled lava, bare rock, newly created ponds or reservoirs and is generally slow |
| C. | Hydrarch Succession | R. | Takes place in wet areas and the series progress from hydric to mesic conditions |
| D. | Xerarch Succession | S. | Occurs in areas where natural biotic communities have been destroyed like abandoned farmlands, burned or cut forests, lands that have been flooded and is faster |
| A | B | C | D | |
| 1. | Q | S | R | P |
| 2. | S | Q | P | R |
| 3. | P | R | Q | S |
| 4. | R | P | S | Q |