The predecessor of 1 lakh is
99000
99999
999999
100001
Step 1: “Predecessor” means the number just before a given number.
Step 2: Write 1 lakh in digits.
\[ 1\text{ lakh} = 100000 \]
Step 3: Find the number just before it by subtracting 1.
\[ 100000 - 1 \]
Step 4: Do the subtraction carefully.
\[ 100000 - 1 = 099999 \]
\[ 099999 = 99999 \]
Answer: \(99999\), which is option B.