One Way to Kill a Tree Is to Girdle It

question 58

Multiple Choice

One way to kill a tree is to girdle it by cutting a groove a centimeter into the bark all around the trunk of the tree.The tree will typically survive that growing season,but will die over the winter.Which is the best explanation for this observation?

• A) The phloem was cut, so water and nutrients cannot be taken up to the leaves.
• B) The xylem was cut, so sugars cannot be transported to the roots.
• C) The xylem was cut, so water and nutrients cannot be taken up to the leaves.
• D) Cutting the bark allows access to pathogens that kill the tree.
• E) The phloem was cut, so sugars cannot be transported to the roots.

---

Definitions:

Primary Key

A primary key is a unique identifier for each record in a database table, used to ensure that each entry is distinct and retrievable.

Principal Key

Another term for primary key, an attribute or set of attributes that uniquely identifies each record in a database table.

Foreign Key

An attribute in a database table that provides a link between data in two tables, typically to enforce referential integrity.

Main Key

A unique identification attribute or field in a database, functionally identical to a primary key.