Look at the following picture and complete the dialog.

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Tono:  Are Mr. Rahman and Mrs. Lina picking vegetables in the garden?

Kana:  ________________________________ (1)

Tono:  What are they doing?

Kana:  _________________________________ (2)

Tono:  What are Mrs. Lina carrying in the plant pots?

Kana:  __________________________________ (3)

Tono:   Where are they planting the vegetable seedlings?

Kana:   __________________________________ (4)

Which sentence is suitable to fill the blank in point (4)?