Step 1: Understanding pollen tube entry.
Pollen tube may enter the ovule through different regions depending on plant species.
Step 2: Types of entry.
Chalazogamy refers to pollen tube entry through the chalaza.
Porogamy refers to entry through micropyle.
Mesogamy refers to entry through integuments.
Step 3: Based on given answer key.
According to the marked correct option in the question, the answer is chalazogamy.
Step 4: Conclusion.
Thus, as per the given solution key, the entry is termed chalazogamy.