The string handling functions FIND and SUBSTRING are defined as follows:

• FIND(target, source): Returns the 0-based index of the first occurrence of the string target within the string source (for example, FIND("B", "ABC") returns 1).
• SUBSTRING(start, length, source): Returns a string of length length from source starting at the 0-based index start (for example, SUBSTRING(1, 2, "ABCDE") returns "BC").

The variable result is assigned a value using the statement:

result ← SUBSTRING(FIND("-", sensor_id) + 1, 4, sensor_id)

Using the configuration values below, what value is assigned to result?

sensor_id ← "TEMP-4029-A"
reading ← "23.85C"
status ← "ACTIVE_OK"